Composite plate

Abstract

A composite plate including a core plate, and top surface and bottom surface metallic plates which are folded to enclose the core plate to provide an airtight seal to the core plate. The composite plate has particular utility for use as a structural plate, such as floor plate, ceiling plate, etc.

What is claimed is: 
     
       1. A relatively light-weight structural member resistant to fire, generation of smoke and impervious to moisture comprising: a substantially flat wood core defined by a top surface, a bottom surface and side surfaces;   top and bottom metallic plates covering said top and bottom surfaces of said wood core and metallic sides integral with said top and bottom plates covering said side surfaces of said wood core;   said top and bottom metallic plates being provided with integral overlapping-sealed joint portions to seal said metallic plates about said wood core; the overlapping parts of said joint portions being bent towards said wood core to form edges which abut one another, said edges being welded together to form a complete seal about said wood core.   
     
     
       2. A structural member according to claim 1, wherein said wood core is provided with a stepped portion at its outer periphery and said metallic plates are joined together at said stepped portion by bending said overlapping joint portions into said stepped portion. 
     
     
       3. A structural member according to claim 2, wherein said metal plates are formed of stainless steel. 
     
     
       4. A structural member according to claim 1, wherein said wood core is formed of plywood.